Combination float shoe and spiral cement mlxer



Nov. 19, 1963 w, w, FERRAR ETAL 3,111,171

COMBINATION FLOAT SHOE AND SPIRAL CEMENT MIXER Filed March 17, 1961WILL/F IK [HIP/PHI? WILL/HM 1?. LIME IN V EN TORS.

United States Patent Ofiice 3,111,171 Patented Nov. 19, 1963 3,111,171COMBINATION FLOAT SHOE AND SPIRAL CEMENT MIXER Willie W. Farrar andWilliam R. Lewis, both Totem Oil Tools, Inc., 6005 Jacltsboro Highway,Wichita Falls,

Tex.

Filed Mar. 17, 1%1, Ser. No. 96,417 2 Claims. (Q1. 166225) Thisinvention relates to an improvement in a float shoe and moreparticularly to a float shoe which is used in connection with thecementing of casing in wells, wherein the cement, which passes outwardfrom the lower end of the float shoe, is given a spiral, swirling actionin order to agitate the cement and to cause the cement to flow evenlyupward in the annulus between the wall of the casing and the wall of thebore hole of the well.

Various float shoes for use in the cementing of casing in wells, such asoil wells, have been proposed heretofore, but these, for the most part,directed the cement downward without regard to the mixing of the cementand water into a slurry, as it is passed outward from the lower end ofthe casing, which would cause improperly mixed cement to be directedaround the casing.

The present device allows the cement to be homogenized into a smoothconsistency as it is directed spirally upward around the casing.

An object of this invention is to provide a float shoe for well casingand the like, which will serve several purposes; that of closing thelower end of the casing to allow the casing to be lowered into amud-filled hole, so that the mud will buoy up the casing to lighten theload of the casing, as the casing, is being run into the hole; that ofexcluding the mud from the interior of the casing, so that the cementrun into the casing will not be diluted with mut; and that if providingfor the spiral discharge of the mud out through the lower end of theplug, when it is desired to force cement downward through the casing andout through the lower end thereof, to fill the annulus between theexterior of the casing and the wall of the well, preparatory toanchoring the casing in the well when the cement has set.

Another object of the invention is to provide a low cost, drillable,metallic float shoe, with a drillable seating valve element therein, sowhen the casing has been anchored in place by cement, the well can bereadily completed by drilling the cement therein and the plug out oi thelower end of the casing.

Still another object of the invention is to provide a float shoe andvalve combination, which is low in the cost of manufacture, and which iseffective as a float shoe and as a cement mixing device.

With these objects in mind, and others which will become manifest as thedescription proceeds, reference is to be had to the accompanyingdrawings, in which like reference characters designate like parts in theseveral views thereof, in which:

MG. 1 is a vertical sectional view through the lower portion of a well,showing a well casing therein having a casing float shoe secured to thelower end thereof, which float shoe is the basis of the presentapplication, the casing and the float shoe being shown in elevation;

FIG. 2 is an enlarged, longitudinal, sectional view through the lowerend of the well casing, showing the float shoe installed thereon, andshowing the ball valve removed, in order to bring out the details ofconstruction, but two positions of the ball valve being shown in dashedoutline;

FIG. 3 is a fragmentary view of the lower end of the float shoe, whichis enlarged further, and particularly showing the opening through thefloat shoe and the spiral fins, as seen through the opening;

FIG. 4 is a top plan view of the float shoe removed from the casing, andshowing the ball valve removed therefrom in order that the details ofconstruction may be readily viewed; and

FIG. 5 is a top plan view, similar to FIG. 4, but with the ball valve inplace.

With more detailed reference to the drawing, the numeral 6 designatesgenerally the lower portion of the bore hole of a well, which bore holehas a casing 8 therein. A float shoe, designated generally at 10, isscrew threaded into the lower end of coupling 12, which coupling 12 issecured on the lower end of casing 8. The float shoe 10 is preferablymade of metallic alloy, the principal material thereof being aluminum,which has been alloyed with other materials so it will be readilydrillable.

The float shoe Ill is screw threaded, as indicated at 14, so as tothreadably engage the lower threaded end of coupling 12, so that theshoulder 16 of the float shoe 10 will abut with the lower end of thecoupling 12, to form a fluid tight joint therewith.

A valve plate 18 is screw threaded into the coupling 12 above the floatshoe 10, so that the axial opening 20 formed in the plate 13 will be inaxial alignment with the opening through the iloat shoe 10. The valveplate 18 has a. valve seat 22 therein, so as to complemcntally seat aspherical ball 24 therein, when the ball 24 is positioned as indicatedat a in FIG. 2, in dashed outline. When the ball is in this position, asthe casing is being run into the well, the ball 24 is buoyed up intoseating relation with seat 22 of the valve plate 18, thereby a portionof the weight of the casing to be buoyed up, is buoyed up by the mud inthe bore hole of the well.

The ball 24 is guided within the float shoe 10 by the upright ribs 2(,the upper ends of which ribs are substantially parallel, but which ribsextend downward in a spiraling manner, which ribs spiral in the samedirection at the lower ends thereof so as to form a seat or restingplace for the ball 24, when the ball 24 is in the position as indicatedat b, in dashed outline. in FIG. 2, so the ball 24 will rest on ribs 2!:to enable the cement to be cir culated downward through the casing andoutward below the ball 24 and through opening 28 in the lower end offloat shoe it). With the ball so positioned, it will not impede the flowof cement through the float shoe.

\Vith the casing S lowered into place within well 6, as to a producingzone 3i such as an oil sand or the like, the casing may be held insuspended relation in the well. by slips or the like, whereupon, amixture of cement and water is introduced into the casing underpressure, the ratio and quantity of which mixture is predetermined.After the slurry mixture of cement and water is introduced into thecasing, a conventional cementing plug (not shown) is attached to ameasuring line and placed in the casing when the last of the cement isrun into the casing. Mud is then pumped into the casing onto thecementing plug to force the cementing plug, the cement slurry and themeasuring line downward until the cementing plug has reached apredetermined depth. within the casing, or until the plug is pumped intoseating engagement with the valve plate 18 within coupling 12 at thelower end of the casing.

In the first instance, if the cementing plug is pumped downward into thecasing under pump pressure exerted on the drilling mud, for a givendistance, for instance within twenty feet of the lower end of thecasing, the measuring line is detached from the cementing plug, as by aspecified number of pulls therein, as is well understood in the drillingart, the cement is then allowed to harden or set, whereupon, thecementing plug, the remaining portion of the cement within the casing,the valve plate 18, which is also made of drillable material, the ballvalve 24 and the float shoe are drilled out and the 3 cement below thecasing is drilled until the well complcted.

The ribs 26. which are formed interiorly of the float shoe 10 are soformed as to give a swirling. spiraling movement to the cement slurry itpasses downwardly in the well casing, which movement will give a bettermix-- ing to the cement by removing the air therefrom, which results ina more dense mixture. This movement also results in a better flow of thecement upward around the casing to cause the mud thereabovc to moveupward within the annulus formed between the exterior of the casing andthe wall of the bore hole, with the cement being forced into the spaceoccupied by the drilling mud as the drilling mud is forced upward.

Having thus clearly illustrated and described the invention, what isclaimed as new and desired to be secured by Letters Patent is:

l. The combination of a float shoe and cement mixer for use on the lowerend of a well casing, comprising a hollow. threaded, cylindrical memberadapted to threadably attach to the lower end of said well casing, avalve seat nttachably positioned within said hollow, threaded,cylindrical member below the lower end of said well casing. a screwthreaded, hollow body having an axial opening formed therethrough, whichhollow body threadably engages the lower end of said hollow, threaded,cylindrical member, a plurality of circunrterentially spaced ribs formedon the inner hollow portion of said hollow body and extending inwardlytoward the axis for a spaced distance, which ribs extend throughout thegreater portion of the length of said hollow, threaded, cylindricalmember, the upper portion of which ribs are substantially verticallyarranged to form upright guideways, the lower portions of which ribsbeing spirally arranged to extend over at least a portion of the loweropening in said hollow body so as to form a ball valve support, a ballvalve fitted within said hollow body so as to rest on the upper side ofthe lower end portions of said support when said ball valve is in oneposition, and which upper portions of said ribs guides s id ball valveto seat upwardly in fluid tight relation on said valve seat when saidball valve is in another position.

2. The combination of. a float shoe and cement mixer for use on thelower end of a Well casing, comprising a hollow, threaded member adaptedto thrcadably attach to the lower end of said Well casing, a valve seatattachably positioned within said hollow, threaded member below thelower end of said well casing, a screw threaded, hollow body having anaxial opening formed therethrough, which hollow body thrcadably engagesthe lower end of said hollow. threaded member. three ci rcum fcrentiallyspaced ribs formed on the inner portion of said hollow body, the upperportion of which ribs form vertical guid ways, the lower portions ofwhich ribs extend inwardly with the respective end portions of said ribsbeing spirally arranged to extend in the same spiral pattern over atleast a portion of the opening at the lower portion of said hollow bodyso as to form a ball valve receiving support, a ball valve fitted withinsaid hollow body so as to rest on said inwardly extending spiral ribswhen said ball. valve is in one position, and which upper, verticalportions of said ribs will guide said ball valve to seat on said valveteat when said ball valve is in another position.

OLeary et al. May 3, 1938 Burt June 18, 1940

1. THE COMBINATION OF A FLOAT SHOE AND CEMENT MIXER FOR USE ON THE LOWEREND OF A WELL CASING, COMPRISING A HOLLOW, THREADED, CYLINDRICAL MEMBERADAPTED TO THREADABLY ATTACH TO THE LOWER END OF SAID WELL CASING, AVALVE SEAT ATTACHABLY POSITIONED WITHIN SAID HOLLOW, THREADED,CYLINDRICAL MEMBER BELOW THE LOWER END OF SAID WELL CASING A SCREWTHREADED, HOLLOW BODY HAVING AN AXIAL OPENING FORMED THERETHROUGH, WHICHHOLLOW BODY THREADABLY ENGAGES THE LOWER END OF SAID HOLLOW, THREADED,CYLINDRICAL MEMBER, A PLURALITY OF CIRCUMFERENTIALLY SPACED RIBS FORMEDON THE INNER HOLLOW PORTION OF SAID HOLLOW BODY AND EXTENDING INWARDLYTOWARD THE AXIS FOR A SPACED DISTANCE, WHICH RIBS EXTEND THROUGHOUT THEGREATER PORTION OF THE LENGTH OF SAID HOLLOW, THREADED, CYLINDRICALMEMBER, THE UPPER PORTION OF WHICH RIBS ARE SUBSTANTIALLY VERTICALLYARRANGED TO FORM UPRIGHT GUIDEWAYS, THE LOWER PORTIONS OF WHICH RIBSBEING SPIRALLY ARRANGED TO EXTEND OVER AT LEAST